Cover for a tablet device

ABSTRACT

Accurate and reliable techniques for determining information of an accessory device in relation to an electronic device are described.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/247,942, filed Sep. 28, 2011, entitled “COVER FOR A TABLET DEVICE”,which is incorporated herein by reference in its entirety for allpurposes.

FIELD

The described embodiments generally relate to accessory devices usedwith portable electronic devices. More particularly, the presentembodiments describe passive and active circuits that can be usedindividually or in combination to identify specific characteristics ofthe accessory device. The identified characteristics can be used by theportable electronic device to alter an operating state of the electronicdevice, identify specific features of the accessory device, and soforth.

BACKGROUND

Recent advances in portable computing includes the introduction of handheld electronic devices and computing platforms along the lines of theiPad™ tablet manufactured by Apple Inc. of Cupertino, Calif. Thesehandheld computing devices can be configured such that a substantialportion of the electronic device takes the form of a display used forpresenting visual content leaving little available space for anattachment mechanism that can be used for attaching an accessory device.

The display can include various user interface features that caninteract with external stimuli to convey information from an end user,for example, and processing circuitry in the hand held computing device.For example, the display can include touch sensitive elements that canbe used to enable various multi-touch (MT) functions. When the accessorydevice takes the form of a cover, the handheld computing device can beoperable in modes consistent with the presence of the cover. Forexample, when the handheld computing device has a display, the presenceof the cover can render the display unviewable. In order to save power,the unviewable display can be rendered temporarily inoperable until thecover is moved or otherwise repositioned to expose the display.

Therefore, accurate and reliable techniques for determining a currentstatus of an accessory device by an electronic device to which it isconnected are desired.

SUMMARY

This paper describes various embodiments that relate to a system,method, and apparatus for passively providing information from anaccessory device to a host device. In one embodiment, the accessorydevice takes the form of a protective cover and the host device takesthe form of an tablet computer.

In one embodiment, a consumer electronic product is described. Theconsumer electronic product consumer electronic product includes atleast an accessory device. The accessory device includes a flap portionhaving at least a passive information element associated with accessorydevice information. The consumer electronic product also includes anelectronic device attached to the accessory device that includes adisplay, and a detection mechanism that detects the presence of thepassive information element only when the flap portion is in proximityto the display. The detection mechanism provides the accessory deviceinformation associated with the detected passive information element tothe processor that uses the accessory device information to alter anoperating state of the electronic device.

In another embodiment a method for altering an operating state of anelectronic device in accordance with accessory device informationassociated with an accessory device is described. The method is carriedout by performing at least the following operations: detecting thepassive information element by a detection mechanism in the electronicdevice, determining the accessory device information based upon thedetecting, and altering the operating state of the electronic device inaccordance with the accessory device information.

Non-transitory computer readable medium for altering an operating stateof an electronic device having a processor and a display are described.The computer readable medium includes at least computer code fordetecting the passive information element by a detection mechanism inthe electronic device, computer code for determining accessory deviceinformation based upon the detecting of the passive information element,and computer code for altering the operating state of the electronicdevice in accordance with the accessory device information.

In yet another embodiment, an accessory device is described. Theaccessory device includes an attachment mechanism for attaching theaccessory device to an electronic device having a display and aprocessor. The accessory device includes at least a flap portion havinga size and shape in accordance with the display and an informationelement. In the described embodiment, the information element isassociated with accessory device information such that when theinformation element is detected by a detection mechanism in theelectronic device. The detection mechanism provides the accessory deviceinformation to the processor. The processor uses the accessory deviceinformation to alter an operating state of the electronic device.Generally, the detection occurs only when the flap portion and thedisplay are in close proximity to each other.

Other aspects and advantages of the invention will become apparent fromthe following detailed description taken in conjunction with theaccompanying drawings which illustrate, by way of example, theprinciples of the described embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be readily understood by the following detaileddescription in conjunction with the accompanying drawings, wherein likereference numerals designate like structural elements, and in which:

FIG. 1 shows a top perspective view of an electronic device inaccordance with the described embodiments.

FIG. 2A shows a first perspective view of the electronic device in theform of a tablet device and the accessory device in the form of aprotective cover.

FIG. 2B shows a second perspective view of the electronic device in theform of a tablet device and the accessory device in the form of aprotective cover.

FIG. 3A shows a closed configuration of the cooperating system formed bythe tablet device and protective cover shown in FIGS. 2A and 2B.

FIG. 3B shows an open configuration of the cooperating system shown inFIG. 3A.

FIG. 4 shows a top view of an embodiment of a segmented cover assembly.

FIG. 5A and FIG. 5B shows segmented cover 300 in partial openconfigurations with respect to tablet device.

FIGS. 6 and 7 show a multi-touch (MT) sensing arrangement.

FIG. 8 shows a representative ungrounded metallic strip in relation to adetection grid of a touch screen in accordance with the describedembodiments.

FIG. 9 shows system that includes protective cover pivotally coupled totablet device in accordance with the described embodiments.

FIG. 10 shows system that includes protective cover pivotally connectedto tablet device in accordance with the described embodiments.

FIG. 11A and FIG. 11B show representative peek mode functionality inaccordance with the described embodiments.

FIGS. 12A and 12B show representative system that includes protectivecover having predetermined cut out regions in accordance with thedescribed embodiments.

FIG. 12C shows representative system that includes capacitively coupleduser interface in accordance with the described embodiments.

FIG. 12C shows representative system that includes capacitively coupleduser interface in accordance with the described embodiments.

FIG. 13 shows a flowchart detailing process in accordance with thedescribed embodiments.

FIG. 14 shows a flowchart detailing process in accordance with thedescribed embodiments.

FIG. 15 is a block diagram of an electronic device suitable for use withthe described embodiments.

DETAILED DESCRIPTION

Reference will now be made in detail to representative embodimentsillustrated in the accompanying drawings. It should be understood thatthe following descriptions are not intended to limit the embodiments toone preferred embodiment. To the contrary, it is intended to coveralternatives, modifications, and equivalents as can be included withinthe spirit and scope of the described embodiments as defined by theappended claims.

The following description relates in general to a mechanism that can beused to identify characteristics of an accessory device used with anelectronic device. In a particular embodiment, the accessory devicetakes the form of a protective cover pivotally connected to theelectronic device in the form of a tablet device having a display. Inone embodiment, the display is configured to sense externally appliedstimuli, such as a touch event, and in response, provide informationthat can be used by the electronic device. For example, the display caninclude multi-touch (MT) functionality well suited for recognizingconcurrently applied multiple input events. In one embodiment, theprotective cover has a flap portion having a size and shape inaccordance with the display. In a particular embodiment, the flapportion can be pivotally attached to a hinge portion. In this way, whencoupled with the tablet device, the flap portion can rotate about thehinge portion in one direction to bring the flap portion in substantialcontact with the display in a closed configuration. Conversely, the flapportion can pivot about the hinge assembly in the other direction toexpose the display, or a portion thereof, in an open configuration. Inone aspect of the open configuration, the flap portion can rotate about360 degrees about the hinge portion in such a way that the flap portioncan come into contact with a rear portion of the tablet device.

The protective cover can provide protection to certain aspects (such asa display) of the tablet device while enhancing the overall look andfeel of the tablet device. The protective cover can include electroniccircuits or other elements (passive or active) that can cooperate withelectronic elements in the tablet device. As part of that cooperation,signals can be passed between the protective cover and the tablet devicethat can, for example, be used to modify operations of the tabletdevice, operations of electronic circuits or elements of the protectivecover, and so forth. In one embodiment, the tablet device can operate ina closed cover mode when the protective cover is detected to be in theclosed configuration and an open cover mode otherwise.

In one embodiment, the display can include a touch sensitive surfacethat can react to a plurality of conductive elements incorporated intothe protective cover. The touch sensitive surface can include a numberof capacitive elements that can capacitively couple with an object, orobjects, on or near the protective layer of the display. The capacitivecoupling can, in turn, provide signals that can be evaluated by aprocessor in the tablet device that can be used by an end-user, forexample, in controlling certain aspects of the operation of the tabletdevice. In one embodiment, the object, or objects, can take the form ofelectrically conductive elements embedded in the flap of the protectivecover. In this way, when the protective cover is brought near or intocontact with the protective layer of the display, the electricallyconductive elements can interact with the capacitive elements providingsignals to the processor.

In one embodiment, the signals provided to the processor can correspondto a size, position, and shape of the electrically conductive objects.Therefore, the size, position, and shape of the electrically conductiveobjects can be associated with information that can be used by theprocessor. The information can, for example, be used by the processor todetermine aspects of the protective cover based upon informationassociated with specific configurations of the conductive objects. Forexample, an orientation of a particular conductive object embedded inthe flap can be associated with an information element, such as a bit(i.e., “0” or “1”). For example, a “leftward” tilt can be associatedwith “0” and a “rightward” tilt can be associated with “1”. It should benoted, however, that in order to avoid any ambiguity, the relativeangles of the rightward and leftward tilts should be maximized inrelation to each other. For example, having tilt angles of +45° and −45°can be well suited to maximize the differential signal and reduce anyinterpretation error. Accordingly, a group of conductive objects havinga coordinated relationship to each other can passively conveyinformation to the processor that can be used to, for example, identifyspecific aspects of the protective cover. Such aspects can include, forexample, color, type, style, and so forth.

In one embodiment, the conductive elements can be metallic. For example,the metallic elements can be formed of aluminum. Besides being a goodconductor, aluminum has the added advantages of being lightweight,inexpensive, and easy to fabricate. It should be noted that the metallicelements can also take many shapes. For example, the metallic elementscan be circular, square, rectangular, etc. In some cases, however, ithas been determined that in most instances, the metallic elements areungrounded (i.e., “float”) since in most implementations (but not all),the metallic elements do not directly connect to a ground plane, such asa chassis ground provided by the tablet device. In this case where themetallic element is not grounded, the capacitive signal can reduced overthose signals provided when the metallic element is grounded. In theungrounded case, therefore, it has been found that detection of theungrounded metallic element can be optimized when the metallic elementtakes on a specific shape that can be associated with a specific signal,or class of signals. For example, when the touch screen includes arectangular grid of capacitive detection nodes and the metallic elementtakes on the shape of an elongated rectangle (also referred to as ametal strip) having a diagonal orientation with respect to thecapacitive detection grid, the signal produced by the capacitivecoupling between the diagonal metal strip and the capacitive detectionnodes can be readily distinguished and therefore reliably detected.

In this way, any number of characteristics of the metallic strips suchas the size, shape, orientation, position, etc. of the diagonal metallicstrips can be used to passively convey information from the flap portionof the protective cover to the processor. This information can then beused by the processor to execute instructions that can be used to carryout any number of operations by the tablet device. The information canalso be used to convey information specific to the protective cover(such as type, color, style, specific serial number). For example,providing N metallic strips can provide 2^(N) bits of information(assuming that the relative orientation of the metallic strip isassociated with a particular value of a bit). Other characteristicsbesides physical orientation can be used to convey information. Forexample, relative size, shape, and ability to form a capacitive couplingwith a capacitive detection node, to name but a few, can be usedindependently or in combination to represent information that can beused by the tablet device.

The electronic device can include a number of sensors in addition tothose used to detect the conductive elements in the flap portion of theprotective cover. These additional sensors can include, for example, aHall Effect sensor (HFX) for detecting and responding to a saturatingmagnetic field, an ambient light sensor (ALS) for detecting ambientlight levels in vicinity of the tablet device, and an image capturedevice such as a camera (still or video). In one embodiment, the ALS caninclude a photosensitive circuit (such as a photodiode) that can respondto varying levels of incident light, typically in the form of ambientlight. Typically, the ALS is configured to detect ambient light. The ALScan, however, be configured to respond to the detection of the ambientlight in many ways. For example, the ALS can respond by providing asignal whenever the photosensitive circuit within the ALS detects anamount (i.e., intensity) of ambient light greater than a pre-definedamount of ambient light. In other words, the threshold amount of ambientlight can be a defined threshold level that can be constant or variabledepending upon the situation at hand.

In some situations, the information provided by the conductive elementsin the flap can be used in conjunction with the signals provided by theother sensors all of which can be evaluated by the processor. Forexample, when the flap portion is initially placed upon the protectivelayer, a magnetic element in the flap portion can be detected by the HFXcausing the processor to disable the display. The disabling of thedisplay not only disables the image producing aspect of the display butany touch sensing aspect as well. Therefore, in order to assureconsistent pattern recognition by the touch sensitive portion of thedisplay with regards to the conductive elements in the flap, theprocessor will generally provide an amount of time between the HFXdetecting the magnetic element in the flap and the disabling of thedisplay to allow a first detected pattern to be stored in a data storagedevice. In another embodiment, while in the closed configuration mode,the processor can periodically enable the display for a short period oftime long enough to reliably capture the conductive element patternembedded in the cover. Although this approach can be expected to usemore power, the reliability of the pattern detection can be improved.

These and other embodiments are discussed below with reference to FIGS.1-15. However, those skilled in the art will readily appreciate that thedetailed description given herein with respect to these figures is forexplanatory purposes only and should not be construed as limiting.

The electronic device can take many forms. For the remainder of thisdiscussion, the electronic device is described in terms of a handheldportable computing device. Accordingly, FIG. 1 shows a top perspectiveview of electronic device 10 in accordance with the describedembodiments. Electronic device 10 can process data and more particularlymedia data such as audio, visual, images, etc. By way of example,electronic device 10 can generally correspond to a device that canperform as a smart phone, a music player, a game player, a visualplayer, a personal digital assistant (PDA), a tablet device and thelike. Electronic device 10 can also be hand held. With regards to beinghandheld, electronic device 10 can be held in one hand while beingoperated by the other hand (i.e., no reference surface such as a desktopis needed). Hence, electronic device 10 can be held in one hand whileoperational input commands can be provided by the other hand. Theoperational input commands can include operating a volume switch, a holdswitch, or by providing inputs to a touch sensitive surface such as atouch sensitive display device or a touch pad.

Electronic device 10 can include housing 12. In some embodiments,housing 12 can take the form of a single piece housing formed of anynumber of materials such as plastic or non-magnetic metal which can beforged, molded, or otherwise formed into a desired shape. In those caseswhere electronic device 10 has a metal housing and incorporates radiofrequency (RF) based functionality, a portion of housing 12 can includeradio transparent materials such as ceramic, or plastic. Housing 12 canbe configured to enclose a number of internal components. For example,housing 12 can enclose and support various structural and electricalcomponents (including integrated circuit chips) to provide computingoperations for electronic device 10. The integrated circuits can takethe form of chips, chip sets, or modules any of which can be surfacemounted to a printed circuit board, or PCB, or other support structure.For example, a main logic board (MLB) can have integrated circuitsmounted thereon that can include at least a microprocessor,semi-conductor memory (such as FLASH), and various support circuits andso on. Housing 12 can include opening 14 for placing internal componentsand as necessary can be sized to accommodate display 16 for presentingvisual content, display 16 being covered and protected by a protectivecover layer. In some cases, display 16 can be touch sensitive allowingtactile inputs that can be used to provide control signals to electronicdevice 10. In some cases, display 16 can be a large prominent displayarea that covers a majority of the real estate on the front of theelectronic device.

Electronic device 10 can include a magnetic attachment system that canbe used to magnetically attach electronic device 10 to at least oneother suitably configured object. The magnetic attachment system caninclude a number of magnetic attachment features distributed within andin some cases connected to housing 12. For example, the magneticattachment system can include first magnetic attachment feature 18 andsecond magnetic attachment feature 20 located on different sides ofelectronic device 10. In particular, first magnetic attachment feature18 can be located in proximity to side wall 12 a of housing 12. Secondmagnetic attachment feature 20 can be located within opening 14 nearside wall 12 b of housing 12. In those embodiments where electronicdevice 10 includes a display with cover glass substantially fillingopening 14, second attachment feature 20 can be placed beneath the coverlayer.

The placement of first magnetic attachment feature 18 at side wall 12 acan facilitate the use of magnetic attachment feature 18 to magneticallyattach electronic device 10 to another suitably configured object suchas another electronic device or an accessory device. Accordingly,without loss of generality, first magnetic attachment feature 18 willhenceforth be referred to as device attachment feature 18. The placementof second magnetic attachment feature 20, on the other hand, canfacilitate the use of second magnetic attachment feature 20 to secureaspects of another device attached to electronic device 10 by way ofdevice attachment feature 18. In this way, the overall attachmentbetween the other device and electronic device 10 can be more securethan attaching through first attachment feature 18 alone. Accordingly,and again without loss of generality, second attachment feature 20 willhenceforth be referred to as securing attachment feature 20. Securingattachment feature 20 can include one or more of magnetic elements 22.When a plurality of magnetic elements is used, the arrangement of theplurality of magnetic elements can be widely varied and can magneticallyinteract with a cooperating feature on another device. In oneembodiment, the plurality of magnetic elements associated with securingfeature 20 can assist in securing at least a portion of another deviceotherwise attached to electronic device 10 by way of device attachmentfeature 18. Electronic device 10 can also include Hall Effect sensor 24and magnetometer circuit 26 in the form of onboard compass 26.

FIG. 2A and FIG. 2B show electronic device 100 presented in terms oftablet device 100 and accessory device 200 is shown as protective cover200 each in perspective top views. These elements may generallycorrespond to any of those previously mentioned. In particular, FIGS. 2Aand 2B shows two perspective views of tablet device 100 and protectivecover 200 in the open configuration. For example, FIG. 2A shows deviceattachment feature 108 included in tablet device 100 and itsrelationship to tablet device 100. FIG. 2B, on the other hand, is theview presented in FIG. 2A rotated about 180° to provide a second view ofattachment feature 202 and its relationship with protective cover 200.

Tablet device 100 can take the form of a tablet computing device such asthe iPad™ manufactured by Apple Inc. of Cupertino, Calif. Referring nowto FIG. 2A, tablet device 100 can include housing 102 that can encloseand support device attachment feature 108. In order to not interferewith the magnetic field generated by device attachment feature 108, atleast that portion of housing 102 nearest device attachment feature 108can be formed of any number of non-magnetic materials such as plastic ornon-magnetic metal such as aluminum. Housing 102 can also enclose andsupport internally various structural and electrical components(including integrated circuit chips and other circuitry) to providecomputing operations for tablet device 100. Housing 102 can includeopening 104 for placing internal components and can be sized toaccommodate a display assembly or system suitable for providing a userwith at least visual content as for example via a display. In somecases, the display assembly can include touch sensitive capabilitiesproviding the user with the ability to provide tactile inputs to tabletdevice 100 using touch inputs. The display assembly can be formed of anumber of layers including a topmost layer taking the form oftransparent cover glass 106 formed of polycarbonate or other appropriateplastic or highly polished glass. Using highly polished glass, coverglass 106 can substantially fill opening 104.

Although not shown, the display assembly underlying cover glass 106 canbe used to display images using any suitable display technology, such asLCD, LED, OLED, electronic or e-inks, and so on. The display assemblycan be placed and secured within the cavity using a variety ofmechanisms. In one embodiment, the display assembly is snapped into thecavity. It can be placed flush with the adjacent portion of the housing.In this way, the display can present visual content that can includevisual, still images, as well as icons such as graphical user interface(GUI) that can provide information the user (e.g., text, objects,graphics) as well as receive user provided inputs. In some cases,displayed icons can be moved by a user to a more convenient location onthe display.

In some embodiments, a display mask can be applied to, or incorporatedwithin or under cover glass 106. The display mask can be used to accentan unmasked portion of the display used to present visual content andcan be used to make less obvious device attachment feature 108 andsecuring attachment feature 20. Tablet device 100 can include variousports that can be used to pass information between tablet device 100 andthe external environment. In particular, data port 109 can facilitatethe transfer of data and power whereas speakers 110 can be used tooutput audio content. Home button 112 can be used to provide an inputsignal that can be used by a processor included in tablet device 100.The processor can use the signal from home button 112 to alter theoperating state of tablet device 100. For example, home button 112 canbe used to reset a currently active page presented by the displayassembly. Tablet device 100 can also include camera assembly 114arranged to capture an image or images. Tablet device 100 can alsoinclude ambient light sensor 116 (ALS) used to detect a level of ambientlight. In one embodiment ALS 116 can be used to set a brightness levelof the display assembly. For example, in a darker environment withlittle ambient light, the readings from ALS 116 can cause a processor intablet device 100 to dim the display assembly. In a brighterenvironment, the display assembly can be made brighter. Tablet devicecan further include compass 118 used to detect external magnetic fieldsthat can help in the determination of a position of tablet device 100.Tablet device 100 can also include Hall Effect (HFX) sensor 120 that canbe used to detect the presence of a magnetic element in when cover 200is placed on top of tablet device 100 in a closed configuration. Anaccelerometer and gyroscope (not shown) can determine any dynamicchanges in the position and orientation of tablet device 100 in realtime.

Protective cover 200 can have a look and feel that complements that ofthe tablet device 100 adding to overall look and feel of tablet device100. Protective cover 200 is shown in FIGS. 2A and 2B attached to tabletdevice 100 in an open configuration in which cover glass 106 is fullyviewable. Protective cover 200 can include flap 202. In one embodiment,flap 202 can have a size and shape in accordance with cover glass 106.Flap 202 can be pivotally connected to accessory attachment feature 204by way of hinge assembly 206 each shown in FIG. 2B. In this way, flap202 can rotate about pivot line 211. The magnetic attachment forcebetween attachment feature 204 and device attachment feature 108 canmaintain protective cover 200 and tablet device 100 in a properorientation and placement vis-a-vis flap 202 and cover glass 106. Byproper orientation it is meant that protective cover 200 can onlyproperly attach to tablet device 100 having flap 202 and cover glass 106aligned in a mating engagement. The mating arrangement between coverglass 106 and flap 202 is such that flap 202 covers substantially all ofcover glass 106 when flap 202 is placed in contact with cover glass 106as shown in FIG. 3A.

Flap 202 can be pivotally connected to hinge assembly 206 that, in turn,can be connected to attachment feature 204. Hinge assembly 206 can, inturn, be coupled to electronic device 100 by way of accessory attachmentfeature 204. In this way, the flap 202 can be used as a protective coverto protect aspects of electronic device 100 such as a display cover 106.Flap 202 can be formed of various materials such as plastic, cloth, andso forth. Flap 202 can be segmented in such a way that a segment of theflap can be lifted to expose a corresponding portion of the display.Flap 202 can also include a functional element that can cooperate with acorresponding functional element in electronic device 100. In this way,manipulating flap 202 can result in an alteration in the operation ofelectronic device 100.

Flap 202 can include magnetic material. For example, magnetic elements207 can be used to magnetically attach to corresponding magneticattachment feature 20 whereas magnetic element 209 can be used toactivate Hall Effect sensor 120 when flap 202 is in position above coverglass 106. In this way, Hall Effect sensor 120 can respond by generatinga signal that can, in turn, be used to alter an operating state ofelectronic device 100. Since the cover can be easily attached directlyto the housing of the tablet device without fasteners, the flap 202 canessentially conform to the shape of electronic device 100. In this way,the cover 200 will not detract or otherwise obscure the look and feel ofelectronic device 100. Flap 202 can also include capacitive elements 208arranged in a defined pattern. Capacitive elements 208 can be detectedby a multi-touch (MT) sensitive layer incorporated in display assembly.When flap 202 is placed upon cover glass 106, the MT sensitive layer canrespond to the presence of capacitive elements 208 by generating a touchpattern consistent with the defined pattern. The defined pattern can beused to convey information to tablet device 100. The information caninclude, for example, aspects and characteristics of protective cover200 such as color, type, style, serial number, and so forth.

In addition to capacitive elements 208, flap 202 can include RFID device210 that can be used to identify protective cover 200. In particular,when protective cover 200 is in the closed configuration, flap 202 canbe in contact with cover glass 106 thereby allowing a RFID sensor withintablet device 100 to “read” RFID device 210. In this way not only canthe indication from Hall Effect sensor 120 be corroborated, but anidentification of protective cover 200 can also be performed.

Although FIGS. 3A and 3B show protective cover 200 and tablet device 100magnetically attached to each other, any form of attachment between flap200 and tablet device 100 is possible. For example, protective cover 200can be formed of a sleeve portion pivotally coupled to flap 202. In thisway, tablet device 100 can be inserted into the sleeve portion and flap202 can then pivot to open and closed configurations without the needfor magnetic attachment. However, for the remainder of this discussionand without loss of generality, it is presumed that protective cover 200and tablet device 100 are magnetically attached to each other.

In particular, FIG. 3A shows a closed configuration in which cover glass106 is fully covered by and in contact with flap 202. Protective cover200 can pivot about hinge assembly 206 from the closed configuration ofFIG. 3A to an open configuration of FIG. 3B. In the closedconfiguration, inner layer of flap 202 can come in direct contact withcover glass 106. In this way, capacitive elements 208 can be detected byMT circuit disposed within the display assembly beneath cover glass 106.Moreover, the MT circuit can detect a pattern, or signature,corresponding to the pattern of capacitive elements 208. In this way,the detection of the pattern can provide information that can be used toidentify various characteristics of protective cover 200. For example, afirst pattern can be a pattern of capacitive elements arranged in apattern that maximizes a difference in capacitive signal between any twoadjacent capacitive. One such pattern can be formed of metallic stripsplaced diagonally with respect to a Cartesian detection grid disposedbeneath cover glass 106. In this way, by associating a specificinformation element (such a binary “1”) with a particular orientation, acorrelated pattern of metallic strips can be used to passively conveyinformation to the processor in tablet device 100. It should be noted,however, that the need to maximize a differential signal betweenadjacent capacitive elements can be achieved by varying not only theorientation, but size, shape, material (by varying the electricalproperties of the various capacitive elements) and so forth.

FIG. 4 shows a top view of a specific embodiment of protective cover 200in the form of segmented cover 300. Segmented cover 300 can include body302. Body 302 can have a size and shape in accordance with tablet device100. Body 302 can be formed from a single piece of foldable or pliablematerial. Body 302 can also be divided into segments separated from eachother by a folding region. In this way, the segments can be folded withrespect to each other at the folding regions. In one embodiment, body302 can be formed layers of material attached to one another forming alaminate structure. Each layer can take the form of a single piece ofmaterial that can have a size and shape in conformance with body 302.Each layer can also have a size and shape that correspond to only aportion of body 302. For example, a layer of rigid or semi-rigidmaterial about the same size and shape of a segment can be attached toor otherwise associated with the segment.

In another example, a layer of rigid or semi-rigid material having asize and shape in accordance with body 302 can be used to providesegmented cover 300 as a whole with a resilient foundation. It should benoted that the layers can each be formed of materials having desiredproperties. For example, a layer of segmented cover 300 that comes incontact with delicate surfaces such as glass can be formed of a softmaterial that will mar or otherwise damage the delicate surface. Inanother embodiment, a material such as micro-fiber can be used that canpassively clean the delicate surface. On the other hand, a layer that isexposed to the external environment can be formed of a more rugged anddurable material such as plastic or leather. In yet another embodiment,capacitive elements 208 can be incorporated within the laminatestructure of cover assembly 300.

In a specific embodiment, segmented body 302 can be partitioned into anumber of segments 304-310 interspersed with thinner, foldable portions312. Each of the segments 304-310 can include one or more insertsdisposed therein. By way of example, the segments can include a pocketregion where the inserts are placed or alternatively the inserts may beembedded within the segments (e.g., insert molding). If pockets used,the pocket region can have a size and shape to accommodate correspondinginserts. The inserts can have various shapes but are most typicallyshaped to conform to the overall look of segmented body 302 (e.g.,rectangular). The inserts can be used to provide structural support forsegmented body 302. That is, the inserts can provide stiffness to thecover assembly. In some cases, the inserts may be referred to asstiffeners. As such, the cover assembly is relatively stiff except alongthe foldable regions that are thinner and do not include the inserts(e.g., allows folding) making segmented cover 300 more robust and easierto handle.

Segments 306, 308, and 310 can include inserts 314, 316, and 318,respectively (shown in dotted lines form). Inserts 314-318 can be formedof rigid or semi-rigid material adding resiliency to body 302. Examplesof materials that can be used include plastics, fiber glass, carbonfiber composites, metals, and the like. Segment 304 can include insert320 also formed of resilient material such as plastic but also arrangedto accommodate magnetic elements 322 some of which can interact withmagnetic elements in table device 100 and more specifically attachmentfeature 20. In some embodiments, at least some of magnetic elements 322can magnetically interact with magnetically attractable element 324 toform useful structures whereas magnetic elements 326 can be used tointeract with magnetically sensitive circuits, such as a Hall Effectsensor, included in tablet device 100. Magnetic elements inserts 314-318can also incorporate capacitive elements 208 that can be sensed by a MTsensitive portion of the display of tablet device 100.

Capacitive elements 208 can be widely varied in both form, material ofmanufacture, electrical characteristics, and so forth. In this way, anamount of information that can be passively conveyed by capacitiveelements 208 can also be widely varied. For example, when capacitiveelements 208 are metallic in nature (such as aluminum), the electricalproperties of capacitive elements 208 can be varied by altering thethickness of the aluminum that forms each capacitive element 208. Byvarying the electrical characteristics, the signature detected by the MTdetection grid in tablet device 100 can be based at least in part uponthe relationship between capacitive signal strength and less on theparticular orientation of the capacitive elements.

FIG. 5A and FIG. 5B shows segmented cover 300 in partial openconfigurations with respect to tablet device 100. By partial openconfiguration it is meant that due to the segmented nature of segmentedcover 300, only a portion of protective layer 106 can be exposed at atime. For example, as shown in FIG. 5A, when segment 304 is lifted,portion 502 of display 16 can be viewed. However, since magneticelements 326 are not detectable by HFX sensor 120, in one embodiment,signals from HFX sensor 120 can be interpreted by a processor in tabletdevice 100 to enable display 16. In this way, patterns of capacitiveelements in those segments (such as segments 306 and 308) that remain incontact with display 16 can be detected. The detected patterns can beused to, for example, identify various characteristics of segmentedcover 300. For example, the information included in the detectedpatterns in segment 306 can provide the processor in tablet device 100with information related to the relative position of segment 306. Forexample, by virtue of the fact that the capacitive elements in segment306 can be detected is a clear indication that segment 306 is inessentially the closed configuration with respect to display 16.However, since HFX sensor 120 is no longer detecting the saturatingmagnetic field from magnetic elements 326, the processor in tabletdevice 100 can deduce that only segment 304 is lifted while all othersegments remain in contact with display 16.

Therefore, using this information, an operating state of tablet device100 can be altered by the processor consistent with the fact that onlysegment 304 is lifted. For example, the processor can displayinformation, such as battery level, time of day, email, etc. only inthat portion 502. This “peek” mode can be very useful. Informationdetected in segment 306 can also be used by tablet device 100 to presentspecific visual content on portion of display 16 that is viewable. Forexample, since only a small portion of display 16 is viewable, theinformation provided by segment 306 can cause tablet device 100 todisplay visual information suitable only for presentation in the small,viewable portion of display 16. Such suitable visual information caninclude information icons related to email received, weather conditionsand so forth.

FIG. 5B shows another partially open situation where in addition tosegment 304, segment 306 has also been lifted. The determination thatonly segments 304 and 306 can be ascertained when it is determined thatcapacitive elements 208 in segment 306 are no longer detected whereascapacitive elements 208 in segment 308 can be detected. In this way,additional display resources can be enabled to provide an enhanceddisplay experience. In addition to using capacitive elements, othersensors can be brought into play. For example, ALS 116 and cameraassembly 114 can be used separately or in combination to determine thatsegment 308 has been lifted based upon amounts of ambient light detected(in the case of ALS 116) and/or periodic image capture events by cameraassembly 114. In another embodiment, capacitive elements 504 can beplaced on the periphery of segmented cover 300 at selected locationsthat correspond with capacitive detection nodes 506 in tablet device100. In this way, the ability to capacitively detect capacitive elements504 by capacitive detection nodes 506 can provide an indication of thestatus of segmented cover 300 in relation to tablet device 100. Inaddition to spatial orientation considerations, capacitive elements 208and 504 can be used to passively convey information to the processor intablet device 100 for further processing. For example, an identificationindicator can be embodied as a pattern of capacitive elements includedin capacitive elements 504. The pattern of capacitive elements canprovide unique information associated with particular protective coverssuch a style, color, date of origin, and so forth.

In those embodiments where display 16 includes touch sensingfunctionality, electronic device 10 can include multi-touch (MT) sensingarrangement 600 shown in FIG. 6. MT sensing arrangement 600 can be usedfor recognizing multiple simultaneous or near-simultaneous touch events.MT sensing arrangement 600 can detect and monitor multiple touchattributes (including, for example, identification, position, velocity,size, shape, and magnitude) across touch sensitive surface 602, at thesame time, or nearly the same time, at different times, or over a periodof time. Touch sensitive surface 602 can provide a plurality of sensorpoints, coordinates, or nodes 604 that function substantiallyindependently of one another and that represent different points on atouch sensitive surface. Sensing nodes 604 can be positioned in a gridor a pixel array, with each sensing point capable of generating a signalat the same time. Sensing nodes 604 can be considered as mapping touchsensitive surface 602 into a coordinate system, for example, a Cartesianor polar coordinate system. To produce a touch screen, the capacitancesensing nodes and other associated electrical structures can be formedwith a substantially transparent conductive medium, such as indium tinoxide (ITO). The number and configuration of sensing nodes 604 can bevaried. The number of sensing nodes 604 generally depends on the desiredresolution and sensitivity. In touch-screen applications, the number ofsensing nodes 604 can also depend on the desired transparency of thetouch screen.

Using a MT sensing arrangement 600, signals generated at nodes 604 oftouch sensitive surface 602 can be used to produce an image of thetouches at a particular point in time. For example, each object (e.g.,finger) in contact with or in proximity to touch sensitive surface 602can produce contact patch area 702, as illustrated in FIG. 7. Each ofcontact patch area 702 can cover several nodes 604. Covered nodes 604can detect the object, while remaining nodes 604 do not. As a result, apixilated image of the touch surface plane (which can be referred to asa touch image, a MT image, or a proximity image) can be formed. Thesignals for each contact patch area 702 can be grouped together. Eachcontact patch area 702 can include high and low points based on theamount of touch at each point. The shape of contact patch area 702, aswell as the high and low points within the image, can be used todifferentiate contact patch areas 702 that are in close proximity to oneanother. Furthermore, the current image can be compared to previousimages to determine how the objects can be moving over time, and whatcorresponding action should be performed in a host device as a resultthereof.

Returning to FIG. 6, many different sensing technologies can be used inconjunction with these sensing arrangements, including resistive,capacitive, optical, etc. In capacitance-based sensing arrangements, asan object approaches touch-sensitive surface 602, a small capacitanceforms between the object and sensing nodes 604 in proximity to theobject. By detecting changes in capacitance at each of the sensing nodes604 caused by this small capacitance, and by noting the position of thesensing nodes, a sensing circuit 606 can detect and monitor multipletouches. The capacitive sensing nodes can be based on self-capacitanceor mutual capacitance. In self-capacitance systems, the “self”capacitance of a sensing point is measured relative to some reference,e.g., ground. Sensing nodes 604 can be spatially separated electrodes.These electrodes are coupled to driving circuitry 608 and sensingcircuitry 606 by conductive traces 612 a (drive lines) and 612 b (senselines). In some self-capacitance embodiments, a single conductive traceto each electrode can be used as both a drive and sense line. In mutualcapacitance systems, the “mutual” capacitance between a first electrodeand a second electrode can be measured. In mutual capacitance sensingarrangements, the sensing nodes can be formed by the crossings ofpatterned conductors forming spatially separated lines. For example,driving lines 612 a can be formed on a first layer and sensing lines 612b can be formed on a second layer 612 b such that the drive and senselines cross or “intersect” one another at sensing nodes 604. Thedifferent layers can be different substrates, different sides of thesame substrate, or the same side of a substrate with some dielectricseparation. Because the drive and sense lines are separated, there is acapacitive coupling node at each “intersection.”

The manner in which the drive and sense lines are arranged can vary. Forexample, in a Cartesian coordinate system (as illustrated), the drivelines can be formed as horizontal rows, while the sense lines can beformed as vertical columns (or vice versa), thus forming a plurality ofnodes that can be considered as having distinct x and y coordinates.Alternatively, in a polar coordinate system, the sense lines can be aplurality of concentric circles with the drive lines being radiallyextending lines (or vice versa), thus forming a plurality of nodes thatcan be considered as having distinct r and angle coordinates. In eithercase, drive lines 612 a can be connected to drive circuit 608, andsensing lines 612 b can be connected to sensing circuit 606.

During operation, a drive signal (e.g., a periodic voltage) is appliedto each drive line 612 a. When driven, the charge impressed on driveline 612 a can capacitively couple to the intersecting sense lines 612 bthrough nodes 604. This can cause a detectable, measurable currentand/or voltage in sense lines 612 b. The relationship between the drivesignal and the signal appearing on sense lines 612 b is a function ofthe capacitance coupling the drive and sense lines, which, as notedabove, can be affected by an object in proximity to node 604.Capacitance sensing circuit (or circuits) 606 can sense sensing lines612 b and can determines the capacitance at each node as described ingreater detail below. As discussed above, drive lines 612 a were drivenone at a time, while the other drive lines were grounded. This processwas repeated for each drive line 612 a until all the drive lines hadbeen driven, and a touch image (based on capacitance) was built from thesensed results. Once all the lines 612 a had been driven, the sequencewould repeat to build a series of touch images.

However, it is also possible to distinguish not only discrete objectssuch as a finger, but it is also possible to distinguish what can bereferred to as a distributed object, or more simply a shape. Forexample, as shown in FIG. 8, ungrounded conductive strip 800 can bedetected by MT 500 based in part upon the fact that conductive strip 800is not grounded, there will be at least some conductive coupling betweennodes 604 along diagonal D whenever, for example, row R is drivenresulting in a signal S being detected by sense detectors S2 through S5concurrently. In this way, even though diagonal conductive strip 800 isungrounded, there is a sufficient correlation between pixels in separaterows that the presence of conductive strip 800 can be reliably detectedas well as its orientation with respect to detection grid 804. In thisway, information can be uniquely associated with various detectablecharacteristics of diagonal conductive strip 800. For example, as shownin FIG. 9, diagonal conductive strip 800 can have orientation O₁relative to touch screen 502 whereas diagonal conductive strip 702 canhave orientation O₂ relative to touch screen 502. Accordingly,information can be associated with both the position and orientations ofdiagonal conductive strip 400 and 402.

FIG. 9 shows system 900 that includes protective cover 902 pivotallycoupled to tablet device 100 in accordance with the describedembodiments. In this embodiment, protective cover 902 can include anumber of segments 904-910 at least some of which can include capacitiveelements arranged in various patterns. For example, capacitive elements912 can take the form of metallic strips (formed of, for example,aluminum) that are incorporated into segment 906 in an first diagonalpattern 914 where at least some of diagonal metallic strips 912 arearranged in an diagonal alternating pattern. In order to maximum thereliability of detection by capacitive detection nodes 604 in display16, each of the diagonal metallic strips 912 are arranged at about 45°in relation to the capacitive detection grid 804 in display 16 formed ofcapacitive detection nodes 604. Referring to first diagonal pattern 914,metallic diagonal strips 912-1 and 912-2 are arranged at about +45° inrelation to the capacitive detection grid 804 in display 16 whereasmetallic diagonal strips 912-3 and 912-4 are rotated 90° with respect tometallic diagonal strips 912-1 and 912-2 and about −45° in relation tothe capacitive detection grid 806. In this way, each of the diagonalmetallic strips can be associated with a specific information element(such as a data bit “1”) that can depend, in part, upon the orientationof the specific diagonal metallic strip with respect to capacitivedetection grid 806. For example, diagonal metallic strip 912-1 can beassociated with information element, or bit, corresponding to “1”, 912-2to “1”, 912-3 to “0”, 912-4 to “0”, and so on. In this way, diagonalcapacitive elements 912 can be associated with data wordD1{1,1,0,0,0,0,1,1}. Likewise capacitive elements 916 in segment 908 canbe associated with data word D2{0,1,0,0,0,1} and capacitive elements 918in segment 910 can be associated with data word D3{1,0,0,1,0,0}. Itshould be noted that the length of the various data words need not bethe same for each segment. Moreover, the capacitive elements themselvescan vary from one segment to another and even vary from within eachsegment. In this way, information can be stored in any number ofdifferent ways in protective cover 902.

FIG. 10 shows system 1000 that includes protective cover 1002 pivotallyconnected to tablet device 1004 in accordance with the describedembodiments. Protective cover 1002 can include perimeter capacitiveelements 1006 arrayed along a perimeter of flap 1008. In this way,capacitive detection circuits 1010 disposed beneath display mask 1012can gather information regardless of the operating state of display 16.For example, when protective cover 1002 is in the closed configuration,display 16 will most likely be disabled thereby also disabling any touchscreen functionality. However, with the presence of perimeter capacitiveelements 1006, tablet device 1004 can still gather information fromperimeter capacitive elements 1006 using perimeter detection circuits1010. In one embodiment, perimeter capacitive elements 1006 can resemblean optical bar code in that information can be stored based upon thespacing, size, and electrical properties of each constituent capacitiveelement. It should be noted that the orientation of each of perimetercapacitive elements 1006 can be either diagonal, or not, in relation tothe detection grid.

For example, due to the proximity of peripheral capacitive elements 1006to an edge of flap 202 and housing 12 of tablet device 100, a path tochassis ground can be formed by the contact of the edge of flap 202 andhousing 12. An electrical contact (s) can be incorporated into at leasta portion of the edge of flap 202 thereby increasing a signal to noiseratio (SNR) of the capacitive signal provided by peripheral capacitiveelements 1006. Therefore, due to the increase in SNR, the necessity forsignal differentiation is reduced eliminating the need to use diagonalpatterns.

The following figures illustrate the use of information provided byinformation elements embedded in a protective cover in identifyingspecific functions that can be carried out by an associated tabletdevice. For example, as illustrated in FIGS. 12A and 12B, coverinformation can be used by the tablet device to provide specific visualinformation at particular locations that correspond to specific features(such as cut outs) of the protective cover. Using the example of the cutout regions, this visual information can be provided even in thosesituations where the protective cover is closed with respect to thetablet device.

FIG. 11A and FIG. 11B shows a situation where information provided byprotective cover 200 can cause tablet device 100 to operate in a peekmode in accordance with the described embodiments. More particularly,FIG. 11A illustrates how information provided by protective cover 100can cause tablet device 100 to operate in a simple peek mode. In thedescribed embodiments, tablet device 100 operates in simple peek modewhen selected icons 1102 or other visual elements can be displayed onlyin viewable portion 1104 of display 16 of tablet device 100. Icons 1102can be simply display type icons or in some instances, some or all oficons 1102 can be user interactive. For example, icon 1102-1 can displaya clock showing the current time whereas icon 1102-2 can representgraphical user interfaces used to modify operations of a media playerfunction performed by tablet device 100. Other icons can include, icon1102-3 representing current weather conditions, icon 1102-4 representinga stock market result, and so on. FIG. 11B, on the other hand,illustrates a more advanced form of peek mode in which additionalfunctionality can be enabled when it is determined that more than apre-determined amount of display 16 is viewable. In this mode,additional information available in portions of protective cover 1100 incontact with display 16 can cause tablet device 100 to alter itsoperating state along the lines disclosed. For example, in an advancedpeek mode, an additional display area that is viewable can be used topresent video 1104 (with overlaid user interface 1102-2 or equivalent),textual data 1106 and so on.

FIGS. 12A and 12B show representative system that includes protectivecover 1200 in accordance with the described embodiments. As shown,protective cover 1200 has portions of flap 1202 with specific regionsremoved. The regions removed can have specific shapes and be positionedin specific locations with respect to display 16. In this way,information provided by protective cover 1200 can cause tablet device100 to present visual content in accordance with the size, shape, andlocations of the cut out regions of protective cover 1200. For example,cut out region 1204 shown in FIG. 12A, can be have a size and shapeassociated with a clock icon whereas cut out region 1206 can be have asize and shape associated with a textual output such as a stock report,email, and so on. Moving on to FIG. 12B, cut out 1208 can have a sizeand shape in accordance with a battery icon used to indicate a currentbattery status. Accordingly, as an end user changes protective covers,specific characteristics of the protective cover can be used to alteroperations of the tablet device in accordance with the specificcharacteristics conveyed by the information embedded in the protectivecover.

FIG. 12C shows representative cover system 1212 that includescapacitively linked user interface 1214 in accordance with the describedembodiments. Capacitively linked user interface 1214 can provide anend-user an easy to access user interface that can used to controlfunctions of tablet device 100. Capacitively linked user interface 1214can include, for example, physical buttons 1216 (such as dome buttons)that can permit an end-user to provide instructions to tablet device100. For example, dome buttons 1216-1 and 1216-3 can be used to providea forward/reverse function whereas dome button 1216-2 can provide apause function or a stop function. In one implement, each physicalbutton 1216 can include terminals in the form of electrical traces orthe like that can be connected to conductive strips inside protectivecover 1200. When any of buttons 1216 is pressed, the terminals can beshorted having the effect of altering an electrical characteristic ofthe conductive strips incorporated within protective cover 1200. Thealtering of the electrical characteristics can be detected by thedetection grid and can be further associated with information that canbe used by the processor in tablet device 100.

For example, when fast forward dome button 1216-1 is pressed, terminalsassociated with button 1216-1 can be shorted having the effect ofaltering a capacitive pattern detected by tablet device 100. The alteredcapacitive pattern can be associated with increasing a play rate ofmedia currently be presented by tablet device 100. On the other hand,pressing pause button 1216-2 can have the effect of pausing (or stoppingand exiting) any current operation currently being carried out by tabletdevice 100. Additional input buttons can include, for example, up/downbutton 1216-4 that can be used to advance or regress chapters, goup/down a level, and so forth.

FIG. 12C shows representative cover system 1212 that includescapacitively linked user interface 1214 in accordance with the describedembodiments. Capacitively linked user interface 1214 can provide anend-user an easy to access user interface that can used to controlfunctions of tablet device 100. Capacitively linked user interface 1214can include, for example, physical buttons 1216 (such as dome buttons)that can permit an end-user to provide instructions to tablet device100. For example, dome buttons 1216-1 and 1216-3 can be used to providea forward/reverse function whereas dome button 1216-2 can provide apause function or a stop function. In one implement, each physicalbutton 1216 can include terminals in the form of electrical traces orthe like that can be connected to conductive strips inside protectivecover 1200. When any of buttons 1216 is pressed, the terminals can beshorted having the effect of altering an electrical characteristic ofthe conductive strips incorporated within protective cover 1200. Thealtering of the electrical characteristics can be detected by thedetection grid and can be further associated with information that canbe used by the processor in tablet device 100.

For example, when fast forward dome button 1216-1 is pressed, terminalsassociated with button 1216-1 can be shorted having the effect ofaltering a capacitive pattern detected by tablet device 100. The alteredcapacitive pattern can be associated with increasing a play rate ofmedia currently be presented by tablet device 100. On the other hand,pressing pause button 1216-2 can have the effect of pausing (or stoppingand exiting) any current operation currently being carried out by tabletdevice 100. Additional input buttons can include, for example, up/downbutton 1216-4 that can be used to advance or regress chapters, goup/down a level, and so forth.

FIG. 13 shows a flowchart detailing process 1300 in accordance with thedescribed embodiments. Process 1300 can be performed by receiving asignal at 1302 from a Hall Effect sensor (HFX) indicating that aprotective cover is in a closed configuration with respect to a displayof a tablet device. At 1304, the processor in the tablet device respondsto the signal from the HFX sensor and disables the display. At 1306, ifthe cover is determined to be identified, and then process 1300 ends,otherwise at 1308 the display is enabled and at 1310, capacitivepatterns embodied within the cover are detected. The detected capacitivepatterns are detected using capacitive sensing circuits in the display.At 1312, once the cover has been identified, then the display isdisabled at 1314 and process 1300 ends.

FIG. 14 shows a flowchart detailing process 1400 in accordance with thedescribed embodiments. Process 1400 can be carried out by performing atleast the following operations by a tablet device associated with afoldable cover. In the described embodiment, process 1400 can start at1402 by determining if the foldable cover is closed with respect to thetablet device. By closed it is meant that the protective cover iscovering and therefore in proximity to a multi-touch (MT) detection griddisposed within the tablet device. For example, when the tablet deviceincludes a display, the display can include MT functionality inaccordance with the MT detection grid. Moreover, the determination ifthe cover is closed or not can be resolved in any suitable manner. Forexample, an optical sensor can detect the presence, or not, of theprotective cover based upon an amount of light detected and based uponthe amount of light deduce whether or not the foldable cover is closedor open.

In any case, once it is determined that the foldable cover is closed, adetermination is made at 1404 if a pattern of information elements isdetected. In one embodiment, the information elements can storeinformation capacitively based upon size, orientation, shape, and soforth of the information elements and the MT detection grid. The patternof information elements can, therefore, be based upon a correlation ofindividual characteristics of each of the information elements. Forexample, when the information element is a diagonal strip of aluminum, arightward tilt can be associated with “1”, whereas a leftward tilt canbe associated with “0”, and vice versa. When a pattern is detected, thenat 1406, a determination is made if the pattern is recognized or not.When the pattern is not recognized, then process 1400 ends, otherwise,at 1408, the recognized pattern is associated with foldable coverinformation. The foldable cover information can include, for example,color, style, manufacture date and location, and so forth. At 1410, thefoldable cover information can then be stored in a data storage devicein the tablet device for future reference. For example, if part of thefoldable cover information includes a serial number, then the serialnumber can be associated with a database of authorized foldable coversthat can be periodically stored and updated in the data storage devicein the tablet device. If the foldable cover serial number does not matchan authorized serial number, then the presumption is that the cover isnot authenticated.

FIG. 15 is a block diagram of an electronic device 1500 suitable for usewith the described embodiments. The electronic device 1500 illustratescircuitry of a representative computing device. The electronic device1500 includes a processor 1502 that pertains to a microprocessor orcontroller for controlling the overall operation of the electronicdevice 1500. The electronic device 1500 stores media data pertaining tomedia items in a file system 1504 and a cache 1506. The file system 1504is, typically, a storage disk or a plurality of disks. The file system1504 typically provides high capacity storage capability for theelectronic device 1500. However, since the access time to the filesystem 1504 is relatively slow, the electronic device 1500 can alsoinclude a cache 1506. The cache 1506 is, for example, Random-AccessMemory (RAM) provided by semiconductor memory. The relative access timeto the cache 1506 is substantially shorter than for the file system1504. However, the cache 1506 does not have the large storage capacityof the file system 1504. Further, the file system 1504, when active,consumes more power than does the cache 1506. The power consumption isoften a concern when the electronic device 1500 is a portable mediadevice that is powered by a battery 1524. The electronic device 1500 canalso include a RAM 1520 and a Read-Only Memory (ROM) 1522. The ROM 1522can store programs, utilities or processes to be executed in anon-volatile manner. The RAM 1520 provides volatile data storage, suchas for the cache 1506.

The electronic device 1500 also includes a user input device 1508 thatallows a user of the electronic device 1500 to interact with theelectronic device 1500. For example, the user input device 1508 can takea variety of forms, such as a button, keypad, dial, touch screen, audioinput interface, visual/image capture input interface, input in the formof sensor data, etc. Still further, the electronic device 1500 includesa display 1510 (screen display) that can be controlled by the processor1502 to display information to the user. A data bus 1516 can facilitatedata transfer between at least the file system 1504, the cache 1506, theprocessor 1502, and the CODEC 1513.

In one embodiment, the electronic device 1500 serves to store aplurality of media items (e.g., songs, podcasts, etc.) in the filesystem 1504. When a user desires to have the electronic device play aparticular media item, a list of available media items is displayed onthe display 1510. Then, using the user input device 1508, a user canselect one of the available media items. The processor 1502, uponreceiving a selection of a particular media item, supplies the mediadata (e.g., audio file) for the particular media item to a coder/decoder(CODEC) 1513. The CODEC 1513 then produces analog output signals for aspeaker 1514. The speaker 1514 can be a speaker internal to theelectronic device 1500 or external to the electronic device 1500. Forexample, headphones or earphones that connect to the electronic device1500 would be considered an external speaker.

The electronic device 1500 also includes a network/bus interface 1511that couples to a data link 1512. The data link 1512 allows theelectronic device 1500 to couple to a host computer or to accessorydevices. The data link 1512 can be provided over a wired connection or awireless connection. In the case of a wireless connection, thenetwork/bus interface 1511 can include a wireless transceiver. The mediaitems (media assets) can pertain to one or more different types of mediacontent. In one embodiment, the media items are audio tracks (e.g.,songs, audio books, and podcasts). In another embodiment, the mediaitems are images (e.g., photos). However, in other embodiments, themedia items can be any combination of audio, graphical or visualcontent. Sensor 1526 can take the form of circuitry for detecting anynumber of stimuli. For example, sensor 1526 can include a Hall Effectsensor responsive to external magnetic field, an audio sensor, a lightsensor such as a photometer, and so on.

The various aspects, embodiments, implementations or features of thedescribed embodiments can be used separately or in any combination.Various aspects of the described embodiments can be implemented bysoftware, hardware or a combination of hardware and software. Thedescribed embodiments can also be embodied as computer readable code ona non-transitory computer readable medium. The computer readable mediumis defined as any data storage device that can store data which canthereafter be read by a computer system. Examples of the computerreadable medium include read-only memory, random-access memory, CD-ROMs,DVDs, magnetic tape, and optical data storage devices. The computerreadable medium can also be distributed over network-coupled computersystems so that the computer readable code is stored and executed in adistributed fashion.

The foregoing description, for purposes of explanation, used specificnomenclature to provide a thorough understanding of the describedembodiments. However, it will be apparent to one skilled in the art thatthe specific details are not required in order to practice the describedembodiments. Thus, the foregoing descriptions of the specificembodiments described herein are presented for purposes of illustrationand description. They are not target to be exhaustive or to limit theembodiments to the precise forms disclosed. It will be apparent to oneof ordinary skill in the art that many modifications and variations arepossible in view of the above teachings.

The advantages of the embodiments described are numerous. Differentaspects, embodiments or implementations can yield one or more of thefollowing advantages. Many features and advantages of the presentembodiments are apparent from the written description and, thus, it isintended by the appended claims to cover all such features andadvantages of the invention. Further, since numerous modifications andchanges will readily occur to those skilled in the art, the embodimentsshould not be limited to the exact construction and operation asillustrated and described. Hence, all suitable modifications andequivalents can be resorted to as falling within the scope of theinvention.

What is claimed is:
 1. A cover system formed of a single piece flap andhaving a first surface and a second surface opposite the first surface,the cover system comprising: a user accessible feature at the firstsurface of the cover, the user accessible feature being arranged toreceive a user applied touch, the user accessible feature having anelectrically conductive trace that is capable of being electricallycoupled with capacitive elements carried between the first and secondsurfaces, the capacitive elements each capable of independentlyproviding a corresponding capacitance signal in an electrically unlinkedstate, wherein in response to the user touch applied to the useraccessible feature, the electrically conductive trace electrically linksthe capacitive elements in an electrically linked state forming acapacitive pattern corresponding to an overall capacitance signal thatis detectable through the second surface.
 2. The cover system as recitedin claim 1, wherein the overall capacitance signal is a super-positionof the capacitance signals from each of the linked capacitive elements.3. The cover system as recited in claim 1, wherein the electricallyconductive trace connects at least one of the capacitive elements to anelectrical ground.
 4. The cover system as recited in claim 3, whereinthe grounded capacitive element is incapable of providing acorresponding capacitance signal.
 5. The cover system as recited inclaim 1, wherein the capacitive pattern is limited to the useraccessible feature.
 6. The cover system as recited in claim 1, whereinthe user accessible feature is a first user accessible feature andwherein the cover system further comprises a second user accessiblefeature different than the first user accessible feature.
 7. The coversystem as recited in claim 6, wherein the second user accessible featurecomprises an electrically conductive trace that is capable ofelectrically being electrically coupled with the capacitive elementscarried between the first and the second surfaces.
 8. The cover systemas recited in claim 1, wherein the user accessible feature is a domeswitch.
 9. The cover system as recited in claim 1, wherein when thecover system is attached to an electronic device having an outerprotective layer that overlays both a display and a capacitancedetector, the single piece flap being capable of overlaying the outerprotective layer in such a way that the second surface is in directcontact with outer protective layer such that the capacitance signaldetector is capable of detecting the capacitance signal through thesecond surface and the outer protective layer.
 10. The cover system asrecited in claim 9, wherein the overall capacitance signal is used tocontrol an operation of the electronic device.
 11. The cover system asrecited in claim 9, wherein the electronic device is a tablet device.12. The cover system as recited in claim 10, wherein the operation ofthe tablet device is a volume control.
 13. The cover system as recitedin claim 9, wherein the cover system is magnetically coupled to theelectronic device.
 14. The cover system as recited in claim 9, whereinthe cover system comprises a pocket having a size and a shape thataccommodates the electronic device.